EP2853187B1 - Manufacture of an endoscope with a light conducting device - Google Patents

Description

The present invention relates to an optical fiber endoscope for directing illumination light to the distal end of the endoscope and methods of making an endoscope.

In medical and technical endoscopy, illumination of the object under consideration is generally required. To generate illumination light with a high luminous flux, separate or source light sources integrated in the proximal end of the endoscope are often used. From the proximal end to the distal end of the endoscope, the illumination light is transmitted by means of one or more bundles of optical fibers.

There is a clear tendency to make the shafts of endoscopes thinner and thinner. In this case, the space available for the optical fibers is getting smaller, and the effort in design and production increases. Conventional constructions and manufacturing processes such as in the publication DE 10 2011 007878 A1 must be questioned and modified or replaced by new ones.

An object of the present invention is to provide an improved method of manufacturing an endoscope and an improved endoscope.

This object is solved by the subject matters of the independent claims.

Further developments are specified in the dependent claims.

Embodiments of the present invention are based on the idea of narrowing a lumen, in which optical fibers are arranged, while the optical fibers are heated to a temperature at which they are plastically deformable, when manufacturing an endoscope. By narrowing the lumen, the optical fibers are fused or welded together. In this case, the optical fibers in particular at the same time with the wall or the walls that limit the lumen, welded. The cross sections of the individual optical fibers are changed and the spaces between the individual optical fibers are reduced. Ideally, within the narrowed lumen, a dense structure of optical fibers each having a hexagonal cross-section is formed in a honeycomb-shaped arrangement.

In a method for manufacturing an endoscope, optical fibers are introduced into a lumen in the endoscope, the optical fibers are heated, the lumen is narrowed and the optical fibers are fused, the narrowing of the lumen and the fusing of the optical fibers occurring at least partially simultaneously.

In particular, the lumen has a circular cross section or a circular cross section or a cross section, the edge of which essentially consists of two circular arc sections with identical or different radii, or a cross section whose edge comprises two or more circular arc sections with different or equal radii, or another Cross-section on. The cross section of the lumen after narrowing is geometrically similar or substantially geometrically similar in particular to the cross section of the lumen prior to narrowing. In particular, the lumen has a straight or curved, elongated and narrow cross-section with a width which varies continuously from one end to the other end in particular, the narrowing of the lumen reduces the width of the cross section of the lumen.

The optical fibers are heated in particular together with the lumen-limiting wall or together with the walls bounding the lumen. The optical fibers are heated in particular by heat conduction starting from a wall bounding the lumen, wherein the wall can be heated by heat conduction, heat radiation or in another way. In particular, the optical fibers comprise an inorganic-non-metallic glass, another inorganic glass, another amorphous material, a polymer or another plastic. The optical fibers are in particular heated to a transition temperature or glass transition temperature or glass transition temperature at which the material of the optical fibers has a rubbery to viscous consistency and / or sufficient ductility to be plastically deformed. The fusing of the optical fibers is in particular caused by the narrowing of the lumen and the resulting mechanical pressure, but may, in particular due to wetting properties of the material of the optical fibers already during or after the heating and before the narrowing of the lumen begin.

With the method, a mechanically robust structure of optical fibers in a lumen can be created in an endoscope. The structure of the optical fibers has in particular only small or no voids more. Small remaining voids can then be filled by a material that melts at lower temperatures than the material of the optical fibers. Thus, an impermeable to water vapor and / or other fluids structure can be provided, which may be particularly suitable for hermetically sealed completion of a volume within the endoscope.

In a method as described here, the narrowing of the lumen and the fusing of the optical fibers take place in particular at the distal end of the endoscope.

In a method as described here, in particular a light entry surface or a light exit surface is formed on the optical fibers in or on the fused region of the optical fibers.

The formation of a structure of optical fibers that is fluid-tight immediately or optionally after filling up of remaining small cavities according to a method as described here makes it possible in particular to form a light exit surface at the distal end of the endoscope. For this purpose, the optical fibers are cut off after heating, narrowing and fusing in particular outside of the endoscope and the cut surface is polished and optionally coated and / or otherwise tempered. As a result, a light exit surface can be created directly from the optical fibers without a further transparent window component or another component which at the same time hermetically seals the endoscope and also prevents penetration of moisture and / or other fluids during autoclaving.

In addition, the method can also be used at the proximal end of the endoscope, in particular for forming a light entry surface for illumination light at a coupling point, to which the endoscope can be coupled by means of a light guide cable with a separate light source. The method can also be carried out at the proximal end of an endoscope such that, without the use of a transparent window component or another additional component, a hermetically sealed light entry surface is formed against the penetration of water vapor or other fluids.

In a method as described here, in particular optical fibers are welded to a lumen limiting wall.

The optical fibers are welded in particular during narrowing of the lumen with one or more walls bounding the lumen. The wall bounding the lumen or the walls delimiting the lumen have, in particular, a surgical stool or another metallic material. The welding or cohesive joining of the optical fibers with the wall or the walls which delimit the lumen, can increase mechanical robustness and help prevent fluids from passing through the narrowed lumen.

In a method as described here, the optical fibers are in particular welded to an outer shaft of the endoscope.

In a method as described here, the optical fibers are in particular welded to an inner shaft of the endoscope.

The outer shaft in particular comprises surgical stainless steel or another metallic material. The outer shaft has in particular before the narrowing of the lumen on the shape of a lateral surface or a section of a lateral surface of a circular cylinder. In particular, the outer shaft forms a large part or the major part of the outer surface of the endoscope.

The inner shaft has in particular a surgical stainless steel or another metallic material. The inner shaft has in particular the shape of a lateral surface or a section of a lateral surface of a circular cylinder. The lumen of the inner shaft is particularly intended for receiving a window component, a lens, a rod lens system, a camera, an ordered bundle of optical fibers and / or other means for transmitting observation light and an image or image signal from the distal end to the proximal end of the endoscope. In particular, the inner shaft defines the lumen for the optical fibers outside the inner shaft for transmitting illumination light from the observation beam path arranged within the inner shaft.

The inner shaft may be arranged concentrically to the outer shaft, so that the lumen for the optical fibers, for example, has a circular cross-section. Alternatively, for example, the inner shaft may be disposed in the outer shaft such that the inner shaft contacts the outer shaft at a point or in a line extending from the proximal end to the distal end.

When narrowing the lumen, at least the outer shaft is deformed at the distal end of the endoscope. For example, the cross section of the outer shaft is reduced.

In a method as described here, the narrowing of the lumen in particular comprises a displacement of two walls delimiting the lumen relative to one another. In particular, the lumen is bounded by an outer shaft and an inner shaft, at least one of which deviates from an ideal circular cylindrical shape at the distal end of the endoscope, the lumen being displaced by displacing the outer shaft relative to the inner shaft in a direction parallel or substantially parallel to an axis of symmetry of the External shaft and / or the inner shaft is narrowed.

In a method as described herein, narrowing includes, in particular, deforming a wall bounding the lumen.

The narrowing of the lumen comprises, in particular, a plastic and permanent deformation of a wall delimiting the lumen.

In a method as described here, the narrowing comprises, in particular, a flanging or tipping of the wall.

The narrowing of the lumen comprises, in particular, crimping or upsetting plastic deformation of a distal edge region of an outer shaft.

An endoscope comprises optical fibers for guiding illumination light to the distal end of the endoscope, wherein the optical fibers are arranged in a lumen, and wherein the optical fibers constrict at least at a location at which the lumen narrows upon fabrication of the endoscope after introduction of the optical fibers into the lumen was fused together.

The endoscope is produced in particular by a method as described here and has corresponding features, properties and advantages.

Brief description of the figures

Figur 1

eine schematische Darstellung eines Endoskops;

Figur 2

eine schematische Schnittdarstellung des distalen Endes eines Endoskops;

Figur 3

eine weitere schematische Schnittdarstellung des distalen Endes des Endoskops aus Figur 2 während seiner Herstellung;

Figur 4

eine schematische Schnittdarstellung des distalen Endes eines weiteren Endoskops;

Figur 5

eine weitere schematische Schnittdarstellung des distalen Endes des Endoskops aus Figur 4 während seiner Herstellung;

Figur 6

eine weitere schematische Schnittdarstellung des distalen Endes des Endoskops aus Figur 4 während seiner Herstellung gemäß einem alternativen Verfahren;

Figur 7

schematische Darstellungen eines Querschnitts von Lichtleitfasern eines Endoskops;

Figur 8

ein schematisches Flussdiagramm eines Verfahrens zum Herstellen eines Endoskops.

Embodiments will be explained in more detail with reference to the accompanying figures. Show it:

FIG. 1

a schematic representation of an endoscope;

FIG. 2

a schematic sectional view of the distal end of an endoscope;

FIG. 3

a further schematic sectional view of the distal end of the endoscope FIG. 2 during its manufacture;

FIG. 4

a schematic sectional view of the distal end of another endoscope;

FIG. 5

a further schematic sectional view of the distal end of the endoscope FIG. 4 during its manufacture;

FIG. 6

a further schematic sectional view of the distal end of the endoscope FIG. 4 during its manufacture according to an alternative method;

FIG. 7

schematic representations of a cross-section of optical fibers of an endoscope;

FIG. 8

a schematic flow diagram of a method for manufacturing an endoscope.

Description of the embodiments

FIG. 1 shows a schematic representation of an endoscope 10 with a proximal end 12 and a distal end 14, between which a long shaft 20 extends. The shaft 20 is particularly straight and rigid, but may alternatively and differently from the illustration in FIG. 1 at least partially curved and / or at least partially flexible. In the shaft 20, optical fibers 60 and an observation beam path 70 are arranged.

The endoscope 10 has at the proximal end 12 a coupling 80 for coupling the proximal end 12 of the endoscope 10 to a light source by means of a light guide cable. The external light source and the fiber optic cable are in FIG. 1 not shown. A proximal end portion 62 of the optical fibers 60 is disposed in the coupling 80 and has a light entry surface 16 for illuminating light transmitted to the endoscope 10 from the aforementioned external light source by means of the aforementioned optical fiber cable. A distal end region 64 of the optical fibers 60 is arranged at the distal end 14 of the endoscope 10 and has a light exit surface 18 there, in particular on a distal end face of the shaft 20.

The endoscope 10 is intended in particular for medical applications. For sterilization, the endoscope 10 should be autoclavable. When autoclaving the endoscope 10 is exposed over a period of several minutes to a few hours of saturated water vapor at overpressure and a temperature of about 400 Kelvin or more. In the endoscope 10 penetrating water vapor or other fluids can damage or destroy the endoscope 10. Therefore, the outer surface of the endoscope 10 must not only be as smooth as possible to prevent sticking of contaminants, but also hermetically sealed to prevent ingress of water vapor and other fluids.

This applies in particular also to the light entry surface 16 at the proximal end 12 and the light exit surface 18 at the distal end 14 of the endoscope 10 FIGS. 2 to 8 illustrated how a smooth or largely smooth and in particular hermetically sealed light exit surface 18 at the distal end 14 of the endoscope 10 can be created. Similarly, a largely smooth and in particular hermetically sealed light entry surface 16 at the proximal end 12 of the endoscope 10 are created.

FIG. 2 shows a schematic sectional view of an embodiment of the distal end 14 of an endoscope 10, as described above with reference to FIG. 1 is shown. The illustrated section plane is parallel to the plane of the drawing FIG. 1 and includes an axis of symmetry 28 of the shaft 20.

The shaft 20 comprises an inner shaft 30 and an outer shaft 40. The inner shaft 30 and the outer shaft 40 each have in particular the shape of a lateral surface or a section of a lateral surface of a circular cylinder and are arranged coaxially with one another. In the annular lumen 46 between the inner shaft 30 and the outer shaft 40 are already above with reference to the FIG. 1 described optical fibers 60 for transmitting illumination light from the coupling 80 at the proximal end 12 (see. FIG. 1 ) is arranged to the distal end 14 of the endoscope 10.

In the lumen 38 of the inner shaft 30 is an observation beam path 70 for transmitting light emitted or remitted from an object to be observed from the distal end 14 to the proximal end 12 (see FIG. FIG. 1 ) of the endoscope 10. The observation beam path comprises in particular a light entrance window 72, a lens 74 and a plurality of rod lenses 76, of which in FIG. 2 only a partial is indicated. The light entry window 72 is joined in particular by soldering or in some other way to the distal edge region 34 of the inner shaft 30 such that the lumen 38 of the inner shaft 30 is hermetically sealed.

The distal edge portion 44 of the outer shaft 40 is deformed by crimping or otherwise upsetting at least in the circumferential direction so that the annular lumen 46 between the distal edge portion 34 of the inner shaft 30 and the distal edge portion 44 of the outer shaft 40 has a reduced (measured in the radial direction ) Has a width and a correspondingly reduced cross-sectional area. Accordingly, the optical fibers 60 in the distal end portion 64 between the distal edge portions 34, 44 of the inner shaft 30 and the outer shaft 40 are compressed and deformed. The optical fibers 60 are in the distal end region 64 in particular so strongly deformed, fused together or welded and welded to the adjacent edge regions 34, 44 of the inner shaft 30 and the outer shaft 40 that they a pore-poor or pore-free and therefore hermetically sealed structure with a smooth surface, the Light exit surface 18 (see. FIG. 1 ) forms.

FIG. 3 shows a further schematic sectional view of the distal end 14 of the endoscope 10 from FIG. 2 , The cutting plane of the FIG. 3 corresponds to the cutting plane of FIG. 2 , In contrast to FIG. 2 shows FIG. 3 the distal end 14 of the endoscope 10 prior to deformation of the distal edge portion 44 of the outer shaft 40 and the resulting compression and deformation of the optical fibers 60.

In the in FIG. 3 In the illustrated situation before the compression and deformation of the optical fibers 60, both the inner shaft 30 and the outer shaft 40 in their distal edge regions 34, 44 each have the shape of a lateral surface of a circular cylinder. After the introduction of the optical fibers 60 in the annular lumen 46 between the outer shaft 40 and the inner shaft 30, the distal edge portion 44 of the outer shaft 40 by a simultaneously or successively on the entire circumference in the radial direction force acting in FIG. 3 indicated by two arrows, plastically and permanently deformed. As a result of this radially acting force, the distal edge region 44 is compressed at least in the circumferential direction up to the in FIG FIG. 2 indicated figure. In this case, the optical fibers in the region between the distal edge regions 34, 44 of the inner shaft 30 and the outer shaft 40 are compressed and deformed.

In order to allow a deformation of the optical fibers 60, a fusion or welding of the optical fibers 60 with each other and in particular a welding of the optical fibers 60 to the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40, the optical fibers 60 and in particular the distal edge regions 34, 44 heated before deformation to a temperature at which the optical fibers 60 are plastically deformable. In the case of glass optical fibers, this temperature is especially within or at the transformation region in which the viscosity of the glass changes from brittle to liquid. In the case of polymeric optical fibers 60, the temperature is in particular in the range of the glass transition temperature of the polymer or above. In the case of different materials of core and cladding of the individual optical fibers 60, the optical fibers are heated in particular to a temperature at which, although the core is still largely non-deformable, but the shell is already plastically deformable.

After plastically deforming the distal edge region 44 of the outer shaft 40 and the optical fibers 60 between the distal edge regions 34, 44, the ends of the optical fibers 60 projecting beyond the distal end 14 of the endoscope 10 are cut off. Thereafter, the optical fibers 60 in the distal end portion 64 and the distal end portions 34, 44 of inner shaft 30 and outer shaft 40 in particular up to a in FIG. 3 Back ground and polished by a dashed line indicated plane to a smooth and optically high-quality light exit surface 18 of the optical fibers 60 (see. FIG. 1 ) to create.

During deformation of the distal edge region 44 of the outer shaft 40 and the optical fibers 60 into their future distal end region 64 (see FIG. FIG. 2 ) and during the described grinding and polishing are in particular the light entrance window 72 and other components of the observation radiation path 70 (see. FIG. 2 ) has not yet inserted into the lumen 38 of the inner shaft 30. Instead, a rod of corresponding cross-section may be temporarily inserted into the lumen 38 of the inner shaft 30 to support the distal edge portion 34 of the inner shaft 30 and prevent plastic deformation of the inner shaft 30.

If the outer shaft 40 before deformation in its future distal edge region 44 as in FIG. 3 indicated in solid lines has the shape of a lateral surface of a circular cylinder, it has the described plastic deformation in FIG. 2 in solid lines indicated shape with a step in its outer surface. To avoid this, the outer shaft 40 may originally be with a in FIG. 3 indicated in dashed lines enlarged cross-section or be provided with an increased wall thickness in its future distal edge region 44. This can, if necessary after a final twisting or grinding, a smooth and stepless outer surface of the distal edge region 44 of the outer shaft 40 allow. The contour of such a smooth and stepless outer surface of the distal edge region is in FIG. 2 indicated by dashed lines.

In addition to that on the basis of FIGS. 2 and 3 shown, at least circumferentially compressive plastic deformation of the distal edge portion 44 of the outer shaft 40, the lumen 46 between the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40 by a tail or other, at least circumferentially expanding plastic deformation of the distal edge portion 34 of Inner shaft 30 are narrowed. For this purpose, for example, before the insertion of the optical path 70 defining optical elements 72, 74, 76 in the lumen 38 of the inner shaft 30 (see. FIG. 2 ), a cone with an acute opening angle is pressed into the distal edge area 34 of the inner shaft 30 in order to widen it.

FIG. 4 shows a schematic sectional view of a distal end 14 of another endoscope 10, which in some features and properties above with reference to FIGS. 1 to 3 resembles shown endoscopes. The cutting plane of the FIG. 4 corresponds to the cutting planes of the FIGS. 2 and 3 , The following describes features and properties in which the endoscope 10, the distal end 14 in FIG. 4 is shown from the above based on the FIGS. 1 to 3 distinguished endoscopes.

The endoscope 10, the distal end 14 in FIG. 4 is different from the above based on the FIGS. 1 to 3 illustrated endoscopes in particular in that it is not formed for a straight line of sight, but for an angle of about 30 degrees between the viewing direction and the longitudinal axis of the shaft 20. Accordingly, the angle between the surface normal of a light entry window 72 in the observation beam path 70 and the longitudinal axis of the shaft 20 is approximately 30 degrees. Accordingly, the light exit surface 18 is inclined and the optical fibers 60 are curved near the light exit surface 18. In particular, the entire end face of the shaft 20 is inclined.

The endoscope 10, the distal end 14 in FIG. 4 is different from the above based on the FIGS. 1 to 3 shown endoscopes further characterized in that the Inner shaft 30 is not arranged concentrically to the outer shaft 40. Instead, the inner shaft 30 is disposed in the outer shaft 40 so that both touch each other in a straight line. Inner shaft 30 and outer shaft 40 may be joined by soldering, welding or in some other way materially in this linear region.

The inner shaft 30 and the outer shaft 40 are curved in their distal end regions 34, 44 such that not only the mentioned curvature of the optical fibers 60 arranged in the lumen 46 between the inner shaft 30 and the outer shaft 40 is predetermined, but also the cross-sectional area of the lumen (in each case based on FIG Cut surfaces perpendicular to the optical fibers 60) decreases distally. As a result, the optical fibers 60 are compressed in their distal end region 64.

By heating the optical fibers 60 to a temperature at which they are at least partially plastically deformable and in particular can be fused together and welded to inner and outer shafts 30, 40, the optical fibers 60 are at least partially fused together in their distal end region 64 or welded and welded to the distal edge portions 34, 44 of inner shaft 30 and outer shaft 40.

The narrowing of the lumen 46 between the distal edge regions 34, 44 of the inner shaft 30 and the outer shaft 40 can take place, in particular, in two different ways, which are described below with reference to FIGS Figures 5 are shown.

FIG. 5 shows a further schematic sectional view of the distal end 14 of the endoscope 10 from FIG. 4 , The cutting plane of the FIG. 5 corresponds to the cutting plane of FIG. 4 , The distal end 14 of the endoscope 10 is in FIG. 5 in a situation or configuration prior to the completion of the endoscope 10 and in particular prior to the narrowing of the lumen 46 between the distal edge regions 34, 44 of the inner shaft 30 and outer shaft 40.

The outer shaft 40 originally has the in FIG. 5 indicated shape of a lateral surface of a circular cylinder. The inner shaft 30 is inserted into the outer shaft 40 and there in particular fastened. The optical fibers 60 are introduced into the lumen 46 between the outer shaft 40 and the inner shaft 30. Thereafter, the outer shaft 40, as indicated by two arrows in FIG. 5 indicated, plastically deformed, until he in FIG. 4 having shown shape. For this purpose, the outer shaft 40 is compressed in its future distal edge region 44, in particular at least in the circumferential direction. In this case, the lumen 46 between outer shaft 40 and inner shaft 30 is narrowed so far that the optical fibers 60 are compressed and at least partially melted or welded together at a previously set sufficiently high temperature and with the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40th weld. Finally, projecting portions of the outer shaft 40 and the optical fibers 60 are cut off and up to the in FIG. 5 abraded and polished by a dashed line indicated plane to a optically high-quality light exit surface 18 (see. FIG. 4 ) to accomplish.

FIG. 6 shows the distal end 14 of the endoscope 10 from FIG. 4 before completion in a procedure that provides an alternative to the above based on the FIG. 5 represents represented method. The cutting plane of the FIG. 6 corresponds to the cutting planes of the FIGS. 2 to 5 ,

In contrast to that on the basis of FIG. 5 As shown, not only the inner shaft 30 but also the outer shaft 40 already has the final intended shape before the optical fibers 60 are introduced into the lumen 46 between the outer shaft 40 and the inner shaft 30. However, the inner shaft 30 is initially and in the in FIG. 6 shown situation relative to the outer shaft 40 moved proximally. Only after the complete introduction of the optical fibers 60 into the lumen 46 between the outer shaft 40 and the inner shaft 30, the inner shaft 30 relative to the outer shaft 40, as in FIG. 6 indicated by an arrow, moved distally until the intended and in FIG. 4 shown relative position of inner shaft 30 and outer shaft 40 is reached. As a result, the lumen 46 between the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40 is narrowed. If during displacement of the inner shaft 30 relative to the outer shaft 40 and the narrowing of the lumen 46th between the distal edge regions 34, 44 of which the optical fibers have a sufficient temperature, they fuse or at least partially fuse together and at least partially weld to the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40.

FIG. 7 FIG. 2 shows two schematic sectional views of sections of the lumen 46 between the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40 (in FIG FIG. 7 : left) and after (in FIG. 7 : right) the narrowing of the lumen 46. The cutting plane is orthogonal to the cutting planes of the FIGS. 2 to 6 and orthogonal to the optical fibers 66, 68.

Each optical fiber has a core 66 and a cladding 68 of materials of different refractive indices. Since the core 66 has a higher refractive index than the cladding 68, light is directed by total reflection in the core 66 of the optical fiber 60. Before narrowing the lumen 46 and the compression of the optical fibers 60 (in FIG. 7 : left), both the core 66 and the cladding 68 of each optical fiber 60 have a substantially circular cylindrical shape.

After narrowing the lumen 46 and the deformation of the optical fibers 60 (in FIG. 7 : right) due to the indicated by arrows forces on the edge regions 34, 44 of the inner shaft 30 and outer shaft 40, the optical fibers 60 in the ideal case, the in FIG. 7 right figure shown on. The outer contours of the cross sections of the sheaths 68 of the optical fibers 60 are hexagonal, adjoin each other directly and in particular are fused or welded together. Insofar as the optical fibers 60 adjoin the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40, they have pentagonal cross sections and are welded to the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40. The optical fibers 60 together with the edge regions 34, 44 of inner shaft 30 and outer shaft 40 form a rigid mechanical unit.

Im in FIG. 7 The ideal case shown on the right is that before the narrowing of the lumen 46 between the distal edge regions 34, 44 of inner shaft 30 and outer shaft 40 (in FIG. 7 : left) existing gaps between the optical fibers 60 completely disappeared. The structure of optical fibers 60 and distal edge portions 34, 44 of inner shaft 30 and outer shaft 40 is hermetically sealed.

If deviating from this ideal case gaps or pores remain, for example due to a non-ideal honeycomb arrangement of the cross sections of the optical fibers 60, these cavities can be subsequently filled with a filling material and sealed. The filler material is introduced in particular in the liquid state into the cavities and cures there, for example due to polymerization. Alternatively, for example, a filler whose melting temperature is lower than the melting temperature of the materials of optical fibers 60, inner shaft 30 and outer shaft 40 in the molten state is introduced into the cavities. As filler glass solder can, but can also serve other suitable Werk- or fillers.

In the in FIG. 7 The cores 66 of the optical fibers 60 have circular cross sections, even after the compression and deformation of the sheaths 68, in the ideal case shown to the right. Circular cross-sections of the cores 66 of the optical fibers 60, even after narrowing the lumen 46 and deforming the optical fibers 60, can be obtained, for example, if the material of the cores 66 has a lower plasticity than the material of the temperature selected during the narrowing of the lumen 46 Coats 68.

FIG. 8 shows a schematic flow diagram of a method for manufacturing an endoscope. The method is also suitable for manufacturing an endoscope having features and properties which are different from those described above FIGS. 1 to 7 differ. Nevertheless, reference numerals from the FIGS. 1 to 7 used by way of example to facilitate the understanding of the method.

In a first step 101, optical fibers 60 are introduced into a lumen in the future endoscope 10. The lumen is in particular a gap between an outer shaft 40 and an inner shaft 30, which may be annular or may have any other shape.

In a second step 102, the optical fibers 60 and, in particular, regions 34, 44 of the future endoscope 10 adjoining the optical fibers are heated to a temperature at which the optical fibers 60 are at least partially plastically deformable, fused or welded together and with which the lumen 46 delimiting wall or the lumen 46 bounding walls 34, 44 can be welded.

In a third step 103, the lumen 46 is narrowed. This is done in particular by plastically deforming at least one wall 34, 44 delimiting the lumen 46 and / or by displacing, pivoting or rotating two walls 34, 44 delimiting the lumen 46 relative to one another.

In a fourth step 104, the optical fibers 60 are at least partially fused or welded together. In a fifth step 105, the optical fibers 60 are at least partially welded to a wall 34, 44 delimiting the lumen 46. The fourth step 104 and the fifth step 105 are carried out in particular at least partially during the narrowing 103 of the lumen 46 and caused by the narrowing 103 of the lumen 46.

In a sixth step 106, a light exit surface 18 of the optical fibers 60 is generated by grinding and polishing in the region of the narrowed lumen 46.

Based on FIGS. 1 to 8 It has been described primarily how optical fibers 60 are compressed at the distal end 14 of an endoscope 10 by narrowing a lumen 46 and fused together and with the lumen-limiting walls 34, 44. Similarly, the optical fibers 60 may be compressed in their proximal end portions 62 by narrowing a lumen and fused or welded together and welded to a wall defining the lumen. For this purpose, the optical fibers are introduced and heated in particular in a metallic sleeve in their future proximal end regions 62. Thereafter, the sleeve is narrowed at least locally by plastic deformation. As a result, the lumen of the sleeve in which the optical fibers 60 are arranged is narrowed, and the optical fibers 60 are fused together or welded to one another and to the sleeve. It creates a mechanical rigid structure of optical fibers and sleeve, which in the above using the FIG. 7 can be hermetically sealed in order to protect the interior of the endoscope 10 from the ingress of water vapor and other fluids.

reference numeral

10

endoscope

12

proximal end of the endoscope 10

14

distal end of the endoscope 10

16

Light entry surface for illumination light at the proximal end 12 of the endoscope 10th

18

Light exit surface for illumination light at the distal end 14 of the endoscope 10th

20

Shaft of the endoscope 10

24

distal end of the shaft 20

28

Symmetry axis of the shaft 20

30

Inner shaft of the endoscope 10

34

distal edge region of the inner shaft 30

38

Lumen of the inner shaft 30

40

Outer shaft of the endoscope 10

44

distal edge region of the outer shaft 40

46

Lumen between outer shaft 40 and inner shaft 30

60

optical fiber

62

proximal end portion of the optical fiber 60

64

distal end portion of the optical fiber 60

66

Core of the optical fiber 60

68

Sheath of the optical fiber 60

70

Observation beam path

72

Light entrance window in the observation beam path 70

74

Lens in the observation beam path 70

76

Rod lens in observation beam path 70

80

A coupling for coupling the proximal end 12 of the endoscope 10 to a light source by means of a light guide cable

101

first step (introducing optical fibers into a lumen)

102

second step (heating the optical fibers)

103

third step (narrowing the lumen)

104

fourth step (fusing the optical fibers)

105

fifth step (welding of the optical fibers with a wall bounding the lumen)

106

sixth step (creating a light exit surface)

Claims (10)

1. Method for production of an endoscope (10), with the following steps:

   introduction (101) of optical fibres (60) into a lumen (46) in the endoscope (10);

   heating (102) of the optical fibres (60);

   narrowing (103) of the lumen (46);

   melting together (104) of the optical fibres (60),

   wherein the narrowing (103) of the lumen (46) and the melting together (104) of the optical fibres (60) take place at least partially at the same time.
2. Method according to the preceding claim, in which the narrowing (103) of the lumen (46) and the melting together (104) of the optical fibres (60) take place at the distal end (14) of the endoscope (10) .
3. Method according to the preceding claim, also with the following step:

   formation (106) of a light admission face (16) or of a light exit face (18) on the optical fibres (60) in or on the molten area (64) of the optical fibres (60).
4. Method according to one of the preceding claims, in which optical fibres (60) are welded (105) to a wall (30, 40) delimiting the lumen (46).
5. Method according to one of the preceding claims, in which the optical fibres (60) are welded to an outer shank (40) of the endoscope (10).
6. Method according to one of the preceding claims, in which the optical fibres (60) are welded to an inner shank (30) of the endoscope (10).
7. Method according to one of the preceding claims, in which the narrowing (103) involves two walls (30, 40), which delimit the lumen (46), being moved relative to each other.
8. Method according to one of the preceding claims, in which the narrowing (103) involves a deformation of a wall (30, 40) that delimits the lumen (46).
9. Method according to the preceding claim, in which the narrowing (103) involves a crimping or curving of the wall (30, 40).
10. Endoscope (10) with a proximal end (12) and a distal end (14), between which there extends a long shank (20),
    which comprises an inner shank (30) and an outer shank (40),
    wherein the inner shank (30) and the outer shank (40) each have in particular the form of a circumferential surface or a portion of a circumferential surface of a circular cylinder and are arranged coaxially with respect to each other, wherein optical fibres (60) for transmitting illumination light are arranged in the circular lumen between the inner shank (30) and the outer shank (40),
    wherein a distal edge area (44) of the outer shank (40) is compressively deformed by crimping or other means, at least in the circumferential direction,
    such that the lumen (46) between a distal edge area (34) of the inner shank (30) and a distal edge area (44) of the outer shank (40) has a reduced width, measured in the radial direction, and a correspondingly reduced cross-sectional area, and
    the optical fibres (60) in the distal end area (64) between the distal edge areas (34, 44) of the inner shank (30) and of the outer shank (40) are melted together.

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